Thursday 31 January 2002 03.35 EST
First published on Thursday 31 January 2002 03.35 EST

When Lotfi Raissi first appeared in London's Bow Street magistrates court, he was described as the key flight instructor of four of the September 11 hijackers, including the suspected ringleader, Mohammad Atta. He would, the US authorities said, most likely be charged with conspiracy to murder and could face the death penalty.

Mr Raissi became the first person to be accused of participating in the attacks on New York and the Pentagon, and his name and face were flashed around the world: he was a key suspect in the biggest investigation in criminal history.

A British prosecutor, representing the US government, said: "We have sufficient evidence to show not just association with the pilots - it goes further than that. We have evidence of active conspiracy-proving correspondence and telecommunications with them as well as video footage of them together. We also have proof that they travelled together."

Now, 18 weeks later, the FBI has yet to bring anything other than minor charges against Mr Raissi and it has privately retreated from its early claims. A British judge has warned that the links between Mr Raissi and the terror attacks are "tenuous" and British security sources have voiced doubts, saying "we must be careful not to make him victim of a lynch mob".

The case of the 27-year-old Algerian pilot - pulled from his bed in a flat in Colnbrook, Slough, at 3am on September 21 and now detained in Belmarsh high security prison - has caused concern that US authorities are holding the British legal system to ransom by insisting that it will eventually find the connection that implicates Mr Raissi in the attacks.

It is a tactic that the magistrate Timothy Workman, sitting at Belmarsh magistrates court, appears to be growing tired of in this extradition case. He has warned that if, by February 12, the US is "unable to give the assurances that further charges of terrorist offences are to be offered, I have to assume that they won't".

The case is being watched closely around Europe as criticism mounts that the US has been over-zealous in its attempts to get to the heart of the al-Qaida network and has infringed the civil rights of detainees in the UK and abroad.

At one of Mr Raissi's first court appear ances, an FBI source said: "We believe he is by far the biggest find we have had so far. He is of crucial importance to us."

But recently, an FBI official told the Washington Post: "We put him in the category of maybe or maybe not, leaning towards probably not. Our goal is to get him back here and talk to him to find out more."

That tactic is in violation of the extradition treaty between the UK and the US which prohibits the Americans from charging Mr Raissi with any matter other than the specific charges on which he has been extradited.

Mr Raissi - who has wept uncontrollably in some court appearances - is currently facing extradition on charges that he lied on an application form for a pilot's licence, omitting to declare knee surgery for an old tennis injury and failing to declare a conviction for theft which dates back to when he was 17. These are technically extraditable offences, punishable in the US by more than a year in prison. Evidence of his involvement in the September 11 attacks may yet be uncovered.

However, the US has scaled back its accusations but maintains that Mr Raissi was the flight instructor of Hani Hanjour, the Saudi pilot who is thought to have flown American Airlines flight 77 into the Pentagon. Mr Raissi maintains that he has never met Hanjour.

An FBI affidavit, seen by the Guardian, says that Mr Raissi was "an associate of Hanjour" and that he "often brought other Middle Eastern males with him for training". It claims that Mr Raissi and Hanjour took flight simulator training at Sawyer Aviation in Arizona together on five days in 1998. But the statement goes on: "Efforts are being made to determine whether it was coincidence that Mr Raissi and Hanjour happened to take training on these five days or whether they undertook this training in concert."

Mr Raissi says they may have used the same flight simulator, but this was not unusual as it was one of the country's cheapest. The FBI admits: "It has not yet been determined whether Mr Raissi and Hanjour actually trained together at Sawyer."

A key part of the American case was the claim that it had video footage of Mr Raissi and Hanjour together in Arizona. Mr Raissi's lawyer, Richard Egan, says this was in fact a poor-quality webcam image of Mr Raissi with his cousin and a friend filmed at his Colnbrook flat and that the video has never been mentioned by the US again.

Prosecutors said that Mr Raissi and Hanjour had been in frequent telephone contact but have yet to provide any proof. A claim that Mr Raissi made calls to a suspected al-Qaida leader using the name Shakur proved to be unfounded when it was discovered that on one of these dates he was in Paddington Green police station.

The FBI says Mr Raissi and Hanjour flew in the same aircraft on March 8 1999. Mr Raissi's defence team say this is not true, that logbooks show that Hanjour flew for 1.5 hours and Mr Raissi flew for 1.7 hours and that the tachometer on the plane tallies with this. They claim that the date of an entry in Mr Raissi's logbook is a mistake, and should say March 9. They hope to confirm this by speaking to the pupil Mr Raissi was instructing on that day and checking his logbook.

Las Vegas connection

The Guardian has seen an invoice which shows that Hanjour rented the plane on March 8 and was the only person who rented it that day. His logbook says his instructor was Amro Hassan, not suspected of involvement in the terrorist plot. Mr Hassan says he and Hanjour flew alone and his logbook also says they flew for 1.5 hours. They did different manoeuvres than those listed on Mr Raissi's logbook.

Mr Raissi's belated honeymoon in Las Vegas has also brought suspicion because it is a city that prosecutors say played a key role in the planning of the September 11 attacks. But there is no proof that he and his wife, Sonia, who were in Las Vegas for a week, were there at the same time as any of the hijackers. From Las Vegas, the couple travelled to Phoenix to stay with friends for a week, then Sonia returned to her job in London and Mr Raissi put in two more weeks on the flight simulator.

Investigators say that while he lived in Phoenix, Mr Raissi shared a flat with a man called Redouane Dahmani. In July last year, Mr Dahmani's number was found in the back of a diary discovered in a flat allegedly used by Abu Doha, an Algerian currently in Belmarsh prison accused of being part of a plot to bomb Los Angeles airport on millennium eve.

Prosecutors have used this as another major link but Mr Raissi's lawyer was told yesterday by anti-terrorist branch sources that they have just established that the book did not belong to Mr Doha and that its owner had no connection to terrorism.

Mr Dahmani, who is currently detained in the US on immigration charges, has said that Mr Raissi was "just a kid I met in the mosque when I moved to Arizona". He added: "I was living my life and he was living his. I never saw anything unusual or anything he was doing wrong."

Ambition

The Raissi family are very westernised by Algerian standards. Lotfi's uncle Karim was chief officer of the anti-terrorism branch in Algiers. His mother, Raeba, actively campaigned against terrorism and received threatening phonecalls as a result. She runs a business centre in Algiers. She has provided copies of bank transactions and wire transfers that show she helped pay for her son's flight training while in the US. The FBI has never claimed evidence that Mr Raissi received funds from al-Qaida.

Mr Raissi's family say he dreamed of being a pilot from the age of four. His father, who was a chief steward with Algerie airline, held a light aircraft pilot's licence and would take his son flying with him.

In November 1996, Mr Raissi moved to Phoenix after seeing an advert in Flight International magazine and qualified as a pilot in 1997, later becoming an instructor.

Mr Raissi left the US when his student visa expired in April 2000, moving to the UK in October 2000 to begin a course to transfer his American qualifications to a European standard. He says he had been using the Phoenix simulator to help clock up the hundreds of flying hours needed to become an airline pilot. To pay for this, he had taken work as a flight instructor.

Sonia Raissi - a French Roman Catholic who once made regular work out of cabaret dancing - was also arrested on September 21, but she was released after five days of questioning. She was fired from her ground-staff job with Air France because of the investigation and lives with her brother-in-law in a council flat under the Heathrow flight path in Heston.

Mohamed Raissi, Lotfi's older brother, was detained for two days. He had been due to start a new job as a cleaning supervisor at Heathrow airport on the morning he was arrested but the offer was withdrawn. As Algerian TV flickers in the background of the flat, Sonia and Mohamed talk of how the case has "destroyed the whole family".

Sonia explains that her husband has never tried to stop her doing anything. "He never asked me to become a Muslim," she says. "He never said 'don't drink, don't smoke'. He never pressured me to do anything I didn't want to. They make him out to be a fanatic but we have got nothing to do with these kind of people."

Mohamed is angry: "At first they said Lotfi was the lead instructor, now they say he was at the same flight school. So what? Even if he did instruct him, what difference would that make? Does that make him a terrorist? How would he know what was in his student's head? All those instructors that trained Mohammed Atta, nothing has happened to them."

The family admits there are some murky elements in Mr Raissi's past. He was charged in 1993 for stealing a briefcase in Heathrow airport, but they say it was a one-time impetuous impulse. He also bought a fake ID card so that he could take on work in Britain as a short-order cook. He failed to disclose the knee surgery on the FAA form, they say, because it had been disclosed to the same doctor on the form the year before.

"Innocent people died in America, but innocent people are paying for crimes they didn't commit," says Mohamed. "People think about Britain and think there's democracy, civilisation, there's human rights. But now, with all these detentions, it's very scary. People should remember, it's not an offence to become a pilot."

· James McLintock, the Scottish charity worker dubbed the "Tartan Taliban" after he was arrested in Pakistan on suspicion of having links with al-Qaida, has been freed by the authorities in Pakistan.

Mr McLintock, 37, had been held since Christmas Eve near a former al-Qaida training camp at Tora Bora, in eastern Afghanistan.